Method of bending readily-breakable metals



Patented J une 16, 1925.

UNITED STATES PATENT OFFICE.

ALEXANDER L. DUVAL DADRIAN, OF WASHINGTON, PENNSYLVANIA.

METHOD OF BENDIN G READILY-BREAKABLE METALS.

No Drawing.

Readily-Breakable Metals, of which the fol:

lowing is a specification.

My invention relates to a method of bending metals, which ordinarily cannot be bent without breakage or liability of breakage, for forming units for electric resistances and the like.

As is Well known, tungsten and molybdenum are very brittle at ow temperatures.

It is known that these metals may be readily bent, when in the form of rods, wires or sheets, without liability of breakage, if they are bent while heated, preferably to a red heat. It is desired that these metals be maintained at a uniform elevated temperature, during bending.

In accordance with my method, a section of tungsten wire of proper length, is taken, one end of which may be attached to a form or mold, of insulating material, this form being adapted to produce the desired shape of the resistance unit. One end of this wire is connected with one pole of the source of current, and the opposite end with the opposite pole. A proper current is then passed through the wire to heat it to a red heat,

and while this temperature is maintained uniform, by the continuous passage of the current therethrough, the wire is bentabout the form into the proper sha The method is not restricte to the use of a form, as the wire maybe bent by any suitable means, and may be bent into any desired shape, such as a coil or the like.

Rods, sheets or the like of the tungsten or Application filed April 26, 1921. Serial No. 464,729.

molybdenum are treated in a similar manner, for bending. By this method the metals may be bent into the proper shapes, 4 without liability of breakage. The metals are allowed to cool in the bent form.

It is to be understood that the embodiment of my invention herewith set forth is to be taken as a preferred example of the 60 same, and that various changes may be resorted to in the order of the steps of the method, and equivalent steps employed, all without departing from the spirit of my invention or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. The herein described method of bonding sections of wire formed of readily breakable metals such as tungsten and molybdenum, which consists in connecting" one end of each section of wire to a form, then passing an electric current through the Wire for heating it to a temperature at, which it may be readily bent without liability of breakage, and bending the wire while thus heated about said form.

2. The herein described method of bend- .ing sections of wire formed of readily breakable metals such as tungsten and molybdenum, which consists in connecting one. end of each section of wire to a form, then passing an electric current through the wire for heating it to a temperature at which it may be readily bent without liability of breakage, and bending the Wire about said form while maintaining the same at the temperature for preventing breakage by continuing the flow of current through the metal while it is being bent.

In testimony whereof I affix my signature.

ALEXANDER L. DUVAl. d'ADRlAN. 

